The Casey Anthony murder trial ground to a sudden stop on Thursday after lead defense attorney Jose Baez questioned whether the defendent’s brother, Lee Anthony might be the father of her deceased 2-year-old daughter, Caylee Anthony.

Casey Anthony (ABC News)

FBI expert Heather Seubert was asked by the judge if she had done a paternity test to eliminate Lee Anthony as the father of Caylee Anthony. The prosecution protested the line of questioning and Judge Belvin Perry called a halt to the proceedings and dismissed the jury to go to lunch.

After the jury exited the court room, attorneys on both sides began arguing over whether the question of Caylee Anthony’s paternity was appropriate. FBI expert Heather Seubert reported to the judge that both Casey Anthony’s brother and her father, George Anthony, had been elimated the possible father of Caylee Anthony. So far, the father of Caylee Anthony remains a mystery.

Judge Perry warned Baez “not to ask questions that will lead to an inference… I’m not even going to venture a guess… as to your motivation.” When the jury returned, they were informed that Lee Anthony’s paternity test was negative, although they were not told that George Anthony’s was also negative.Â Most of theÂ rest of the day’s testimony focused on details of the physical evidence found at the scene where Caylee Anthony’s body was found.

Anthony has been accused of murdering the 2-year-old toddler, hiding Caylee Anthony’s body in the trunk of her car and then dumping the body in a wooded area near her home.

Casey Anthony’s defense team argues that Caylee Anthony drowned by accident in the family pool. They claim that after the accidental death, Casey Anthony hid the child’s death as a way to ‘cope’ after suffering years of sexual abuse by her father and brother. George Anthony has repeatedly denied that his daughter suffered any kind of abuse at his or her brother’s hands.